The medical industry employs numerous pieces of complex electronic equipment which must be operated safely so as not to cause injury to the technicians operating the equipment or to patients with whom it is brought into contact. The International Electro-Technical Commission (IEC) has been formed to establish uniform standards for testing such equipment throughout the European countries, and U.S. manufacturers of electronic equipment for the medical industry who want to sell their products in the European market must determine whether their equipment meets the safety standards as established by the IEC. The IEC 601-1 Universal Medical Equipment Safety Standards, which have recently issued, are currently being adopted by all developed countries of the world, and manufacturers of electronic equipment for the medical industry are in need of a device to carry out certain of the new tests required by these standards.
The new Medical Equipment Safety Testing Standards (IEC Standards) require, among other things, that the voltage between the various connector pins of a male connector for an electronic piece of equipment have a voltage which does not exceed 60 volts when measured one second after being disconnected from a source of AC current the test conducted with an instrument, the internal impedance of which does not affect the test. The standard requires that the test be performed 10 times with a voltage across the connector pins not exceeding 60 volts during any of the 10 measurements. Measurements are to be taken across the high voltage and low voltage pins, across the high voltage and ground pins and across the low voltage and ground pins.
The standards further provide that in the event more than 60 volts remain across any of the pins of a piece of equipment one second after it is disconnected from a source of AC power, the energy stored within the device should be tested by a measurement across the connector pins taken one second after the device is disconnected from a source of AC power, and the stored energy should be less than 2 milli-joules.
The standards also require that live capacitors of a circuit which become accessible after an access cover has been removed shall not have a residual voltage exceeding 60 volts, or if this value is exceeded, not have a residual energy of 2 milli-joules.
Presently, there is no equipment available to undertake the tests to determine whether the standards set by the IEC for a piece of equipment have been met, and manufacturers are manually connecting the appropriate meters across connector pins to determine whether their equipment will meet the standards of the IEC. Therefore, it would be desirable to provide a device capable of measuring the residual voltage and power across the contacts of a piece of equipment after it has been disconnected from a source of AC power in order that it may determine if the device complies with the standards as set by the IEC.